1. Field of Invention
This invention relates generally to tank heaters for keeping internal combustion engines warm during cold weather, and pertains more particularly to a catalytic heater.
2. Description of the Prior Art
Catalytic heaters for maintaining the cooling systems of internal combustion engines warm during cold weather, particularly those associated with various types of vehicles, is not new. Examples of such heaters are to be found in U.S. Pat. No. 3,796,207, issued on March 12, 1974 to Ellis W. Olson for "Catalytic Tank Heater for Engines" and U.S. Pat. No. 3,501,257, issued on March 17, 1970 to Chester W. Hilton and Walter E. Hebert for "Heater for Automobile Cooling System," the present applicant being one of the patentees in said Pat. No. 3,501,257. Both of the patented heaters possess certain shortcomings that have detracted from their usefulness. Nonetheless, the two patented heaters serve as examples of prior art constructions.